Abstract: A method and apparatus for controlling a composite battery charger including a switching regulator and a linear charger charging a battery connected to it, whereby the switching regulator provides the supply voltage for the linear charger and Device Circuits. The control method and circuit fully turns on the pass device of the linear charger in a constant current operating mode and the switching regulator is controlled to maintain a constant charge current through the pass device while also supplying device current to the Device Circuits. The device current may vary. The method and circuit limits the dissipation of the pass device of the linear charger by reducing the supply voltage as a function of the charge current in the CC/CV transition region of the battery charger and by reducing the charge current as a function of the battery voltage if the battery voltage is below a predetermined value related to a predetermined minimum supply voltage value.

Abstract: An adaptive pulse positioning system for a voltage converter including an adjustable ramp generator, a pulse generator circuit, and a sense and adjust circuit. The adjustable ramp generator has an adjust input and provides a periodic ramp voltage having an adjustable magnitude based on an adjust signal provided to the adjust input. The pulse generator circuit receives the ramp voltage and generates a pulse signal with control pulses for controlling the output voltage of the voltage controller based on the ramp voltage. The sense and adjust circuit senses an output load transient and provides the adjust signal to the adjust input of the ramp generator to adaptively shift the pulse signal in time in response to the output load transient without adding pulses to the pulse signal.

Abstract: An adaptive pulse positioning system for a voltage converter including an adjustable ramp generator, a pulse generator circuit, and a sense and adjust circuit. The adjustable ramp generator has an adjust input and provides a periodic ramp voltage having an adjustable magnitude based on an adjust signal provided to the adjust input. The pulse generator circuit receives the ramp voltage and generates a pulse signal with control pulses for controlling the output voltage of the voltage controller based on the ramp voltage. The sense and adjust circuit senses an output load transient and provides the adjust signal to the adjust input of the ramp generator to adaptively shift the pulse signal in time in response to the output load transient without adding pulses to the pulse signal.

Abstract: A saturation detection and warning circuit having an adaptive threshold voltage is disclosed. The disclosed circuit can also be used to detect the impending drop out of the low drop out linear voltage regulator. A clamp circuit that clamps the amplifier's output voltage at a voltage that is separated from the adaptive threshold of the saturation detector and warning circuit by a controlled offset voltage is also disclosed.

Abstract: Various embodiments provide a system comprising a regulator and one or more low-drop-out linear regulators for improved efficiency. In one embodiment, a system comprises a regulator and one low-drop-out linear regulator comprising a pass transistor, and furthermore, another transistor matched to the pass transistor except for size. The matching transistor provides information regarding the source-drain voltage drop of the pass transistor. A controller circuit makes use of this information to set the regulator's output voltage to improve the efficiency of the system. Other embodiments are described and claimed.

Abstract: In one embodiment, an amplifier to drive a load in response to an input voltage signal, the amplifier including a first amplifier to drive the load, a second amplifier, and a control sub-circuit to put the second amplifier into an active mode to drive the load when the output voltage of the first amplifier falls outside a voltage window, and to put the second amplifier into an inactive mode when the output voltage of the first amplifier falls within the voltage window. An embodiment also includes a switch to de-couple a capacitive impedance from the load after the second amplifier is put into its active mode, and to couple the capacitive impedance to the load when the output voltage of the first amplifier falls within the voltage window. Other embodiments are described and claimed.

Abstract: A saturation detection and warning circuit having an adaptive threshold voltage is disclosed. The disclosed circuit can also be used to detect the impending drop out of the low drop out linear voltage regulator. A clamp circuit that clamps the amplifier's output voltage at a voltage that is separated from the adaptive threshold of the saturation detector and warning circuit by a controlled offset voltage is also disclosed.

Abstract: Various embodiments provide a system comprising a regulator and one or more low-drop-out linear regulators for improved efficiency. In one embodiment, a system comprises a regulator and one low-drop-out linear regulator comprising a pass transistor, and furthermore, another transistor matched to the pass transistor except for size. The matching transistor provides information regarding the source-drain voltage drop of the pass transistor. A controller circuit makes use of this information to set the regulator's output voltage to improve the efficiency of the system. Other embodiments are described and claimed.

Abstract: In one embodiment, an amplifier to drive a load in response to an input voltage signal, the amplifier including a first amplifier to drive the load, a second amplifier, and a control sub-circuit to put the second amplifier into an active mode to drive the load when the output voltage of the first amplifier falls outside a voltage window, and to put the second amplifier into an inactive mode when the output voltage of the first amplifier falls within the voltage window. An embodiment also includes a switch to de-couple a capacitive impedance from the load after the second amplifier is put into its active mode, and to couple the capacitive impedance to the load when the output voltage of the first amplifier falls within the voltage window. Other embodiments are described and claimed.

Abstract: A tool is described to aid in the design and verification of multi-input, multi-output power supply systems. The designer describes the system requirements and constraints to the tool, which allows an iterative exploration of various alternative designs that satisfy the requirements and constraints. Alternative designs may comprise different power supply topologies, multiple controllers or multi-controllers, or configurable controllers that implement the power supply system. The tool generates a design for a power supply system that is reconfigurable to allow for performance optimization. The power supply system is configurable automatically according to a digital control signal. The digital control signal comprises configuration data which establishes the structure of the power supply system, and which determines the output power conditions of the power source.

Abstract: A tool is described to aid in the design and verification of multi-input, multi-output power supply systems. The designer describes the system requirements and constraints to the tool, which allows an iterative exploration of various alternative designs that satisfy the requirements and constraints. Alternative designs may comprise different power supply topologies, multiple controllers or multi-controllers, or configurable controllers that implement the power supply system. The tool generates a design for a power supply system that is reconfigurable to allow for performance optimization. The power supply system is configurable automatically according to a digital control signal. The digital control signal comprises configuration data which establishes the structure of the power supply system, and which determines the output power conditions of the power source.

Abstract: Improved controller circuitry for a switching power supply is disclosed. The switching power supply is of the type having a transformer having primary and secondary windings for generating an output voltage at the secondary winding, a power switch for driving the primary winding, and controller circuitry for activating the power switch. The improved controller circuitry includes an oscillator and frequency shift means. The oscillator generates PWM pulses having a predetermined frequency for use in activating the power switch. The frequency shift means gradually shifts the frequency of the PWM pulses at a shift rate in response to the output voltage decreasing to below a threshold level. In another embodiment, a controller for use in a switching power supply includes an oscillator for generating PWM pulses having a predetermined frequency which determine the switching condition of the supply.